From 3d9c8f6b3f033a6092425b7344647fb51dbed5c6 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Sun, 26 Aug 2018 14:23:38 +0930 Subject: [PATCH] Delay evaluation of alignment expressions in output sections git commit 702d16713 broke expressions using CONSTANT(COMMONPAGESIZE) in ALIGN or SUBALIGN of output section statements, because these optional fields were evaluated at script parse time and the patch in question delayed setting of config.commonpagesize. The right thing to do is keep the tree representation of those fields for later evaluation. PR 23571 * ldlang.h (section_alignment): Make it an expression tree. (subsection_alignment): Likewise. * ldlang.c (topower): Delete. (output_section_statement_newfunc): Adjust initialization. (init_os): Evaluate section_alignment. (lang_size_sections_1): Likewise. (size_input_section): Evaluate subsection_alignment. (lang_enter_output_section_statement): Don't evaluate here. (lang_new_phdr): Use exp_get_vma rather than exp_get_value_int. * ldexp.h (exp_get_value_int): Delete. (exp_get_power): Declare. * ldexp.c (exp_get_value_int): Delete. (exp_get_power): New function. * emultempl/pe.em (place_orphan): Build expression for section alignment. * emultempl/pep.em (place_orphan): Likewise. * testsuite/ld-scripts/pr23571.d, * testsuite/ld-scripts/pr23571.t: New test. * testsuite/ld-scripts/align.exp: Run it. --- ld/ChangeLog | 23 +++++++++++++++ ld/emultempl/pe.em | 2 +- ld/emultempl/pep.em | 2 +- ld/ldexp.c | 20 +++++++++++-- ld/ldexp.h | 4 +-- ld/ldlang.c | 48 +++++++++++-------------------- ld/ldlang.h | 4 +-- ld/testsuite/ld-scripts/align.exp | 4 +++ ld/testsuite/ld-scripts/pr23571.d | 10 +++++++ ld/testsuite/ld-scripts/pr23571.t | 11 +++++++ 10 files changed, 88 insertions(+), 40 deletions(-) create mode 100644 ld/testsuite/ld-scripts/pr23571.d create mode 100644 ld/testsuite/ld-scripts/pr23571.t diff --git a/ld/ChangeLog b/ld/ChangeLog index 5488c85a0dd..96232df3f3a 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,26 @@ +2018-08-26 Alan Modra + + PR 23571 + * ldlang.h (section_alignment): Make it an expression tree. + (subsection_alignment): Likewise. + * ldlang.c (topower): Delete. + (output_section_statement_newfunc): Adjust initialization. + (init_os): Evaluate section_alignment. + (lang_size_sections_1): Likewise. + (size_input_section): Evaluate subsection_alignment. + (lang_enter_output_section_statement): Don't evaluate here. + (lang_new_phdr): Use exp_get_vma rather than exp_get_value_int. + * ldexp.h (exp_get_value_int): Delete. + (exp_get_power): Declare. + * ldexp.c (exp_get_value_int): Delete. + (exp_get_power): New function. + * emultempl/pe.em (place_orphan): Build expression for section + alignment. + * emultempl/pep.em (place_orphan): Likewise. + * testsuite/ld-scripts/pr23571.d, + * testsuite/ld-scripts/pr23571.t: New test. + * testsuite/ld-scripts/align.exp: Run it. + 2018-08-24 Chenghua Xu * testsuite/ld-mips-elf/mips-elf-flags.exp diff --git a/ld/emultempl/pe.em b/ld/emultempl/pe.em index 463b85481d8..663d4ce8620 100644 --- a/ld/emultempl/pe.em +++ b/ld/emultempl/pe.em @@ -2165,7 +2165,7 @@ gld_${EMULATION_NAME}_place_orphan (asection *s, &add_child); if (bfd_link_relocatable (&link_info)) { - os->section_alignment = s->alignment_power; + os->section_alignment = exp_intop (1U << s->alignment_power); os->bfd_section->alignment_power = s->alignment_power; } } diff --git a/ld/emultempl/pep.em b/ld/emultempl/pep.em index 1a7394ea465..1dc1664f985 100644 --- a/ld/emultempl/pep.em +++ b/ld/emultempl/pep.em @@ -1962,7 +1962,7 @@ gld_${EMULATION_NAME}_place_orphan (asection *s, &add_child); if (bfd_link_relocatable (&link_info)) { - os->section_alignment = s->alignment_power; + os->section_alignment = exp_intop (1U << s->alignment_power); os->bfd_section->alignment_power = s->alignment_power; } } diff --git a/ld/ldexp.c b/ld/ldexp.c index 4ca812e9b20..e123f0e35fe 100644 --- a/ld/ldexp.c +++ b/ld/ldexp.c @@ -1523,10 +1523,26 @@ exp_get_vma (etree_type *tree, bfd_vma def, char *name) return def; } +/* Return the smallest non-negative integer such that two raised to + that power is at least as large as the vma evaluated at TREE, if + TREE is a non-NULL expression that can be resolved. If TREE is + NULL or cannot be resolved, return -1. */ + int -exp_get_value_int (etree_type *tree, int def, char *name) +exp_get_power (etree_type *tree, char *name) { - return exp_get_vma (tree, def, name); + bfd_vma x = exp_get_vma (tree, -1, name); + bfd_vma p2; + int n; + + if (x == (bfd_vma) -1) + return -1; + + for (n = 0, p2 = 1; p2 < x; ++n, p2 <<= 1) + if (p2 == 0) + break; + + return n; } fill_type * diff --git a/ld/ldexp.h b/ld/ldexp.h index d58cacba1c5..094911127ec 100644 --- a/ld/ldexp.h +++ b/ld/ldexp.h @@ -229,8 +229,8 @@ void exp_print_tree (etree_type *); bfd_vma exp_get_vma (etree_type *, bfd_vma, char *); -int exp_get_value_int - (etree_type *, int, char *); +int exp_get_power + (etree_type *, char *); fill_type *exp_get_fill (etree_type *, fill_type *, char *); bfd_vma exp_get_abs_int diff --git a/ld/ldlang.c b/ld/ldlang.c index 350baf2912f..8878ccdb636 100644 --- a/ld/ldlang.c +++ b/ld/ldlang.c @@ -1199,8 +1199,8 @@ output_section_statement_newfunc (struct bfd_hash_entry *entry, ret = (struct out_section_hash_entry *) entry; memset (&ret->s, 0, sizeof (ret->s)); ret->s.header.type = lang_output_section_statement_enum; - ret->s.output_section_statement.subsection_alignment = -1; - ret->s.output_section_statement.section_alignment = -1; + ret->s.output_section_statement.subsection_alignment = NULL; + ret->s.output_section_statement.section_alignment = NULL; ret->s.output_section_statement.block_value = 1; lang_list_init (&ret->s.output_section_statement.children); lang_statement_append (stat_ptr, &ret->s, &ret->s.header.next); @@ -2193,8 +2193,9 @@ init_os (lang_output_section_statement_type *s, flagword flags) exp_init_os (s->load_base); /* If supplied an alignment, set it. */ - if (s->section_alignment != -1) - s->bfd_section->alignment_power = s->section_alignment; + if (s->section_alignment != NULL) + s->bfd_section->alignment_power = exp_get_power (s->section_alignment, + "section alignment"); } /* Make sure that all output sections mentioned in an expression are @@ -4706,8 +4707,10 @@ size_input_section is greater than any seen before, then record it too. Perform the alignment by inserting a magic 'padding' statement. */ - if (output_section_statement->subsection_alignment != -1) - i->alignment_power = output_section_statement->subsection_alignment; + if (output_section_statement->subsection_alignment != NULL) + i->alignment_power + = exp_get_power (output_section_statement->subsection_alignment, + "subsection alignment"); if (o->alignment_power < i->alignment_power) o->alignment_power = i->alignment_power; @@ -5147,7 +5150,8 @@ lang_size_sections_1 section_alignment = os->bfd_section->alignment_power; } else - section_alignment = os->section_alignment; + section_alignment = exp_get_power (os->section_alignment, + "section alignment"); /* Align to what the section needs. */ if (section_alignment > 0) @@ -5225,7 +5229,8 @@ lang_size_sections_1 only align according to the value in the output statement. */ if (os->lma_region != os->region) - section_alignment = os->section_alignment; + section_alignment = exp_get_power (os->section_alignment, + "section alignment"); if (section_alignment > 0) lma = align_power (lma, section_alignment); } @@ -6673,25 +6678,6 @@ lang_add_output (const char *name, int from_script) } } -static int -topower (int x) -{ - unsigned int i = 1; - int l; - - if (x < 0) - return -1; - - for (l = 0; l < 32; l++) - { - if (i >= (unsigned int) x) - return l; - i <<= 1; - } - - return 0; -} - lang_output_section_statement_type * lang_enter_output_section_statement (const char *output_section_statement_name, etree_type *address_exp, @@ -6727,10 +6713,8 @@ lang_enter_output_section_statement (const char *output_section_statement_name, einfo (_("%F%P:%pS: error: align with input and explicit align specified\n"), NULL); - os->subsection_alignment = - topower (exp_get_value_int (subalign, -1, "subsection alignment")); - os->section_alignment = - topower (exp_get_value_int (align, -1, "section alignment")); + os->subsection_alignment = subalign; + os->section_alignment = align; os->load_base = ebase; return os; @@ -7748,7 +7732,7 @@ lang_new_phdr (const char *name, n = (struct lang_phdr *) stat_alloc (sizeof (struct lang_phdr)); n->next = NULL; n->name = name; - n->type = exp_get_value_int (type, 0, "program header type"); + n->type = exp_get_vma (type, 0, "program header type"); n->filehdr = filehdr; n->phdrs = phdrs; n->at = at; diff --git a/ld/ldlang.h b/ld/ldlang.h index 3d661696873..dfac0b1b68e 100644 --- a/ld/ldlang.h +++ b/ld/ldlang.h @@ -143,6 +143,8 @@ typedef struct lang_output_section_statement_struct fill_type *fill; union etree_union *addr_tree; union etree_union *load_base; + union etree_union *section_alignment; + union etree_union *subsection_alignment; /* If non-null, an expression to evaluate after setting the section's size. The expression is evaluated inside REGION (above) with '.' @@ -153,8 +155,6 @@ typedef struct lang_output_section_statement_struct lang_output_section_phdr_list *phdrs; unsigned int block_value; - int subsection_alignment; /* Alignment of components. */ - int section_alignment; /* Alignment of start of section. */ int constraint; flagword flags; enum section_type sectype; diff --git a/ld/testsuite/ld-scripts/align.exp b/ld/testsuite/ld-scripts/align.exp index f9523d26af6..25d4f6dfed5 100644 --- a/ld/testsuite/ld-scripts/align.exp +++ b/ld/testsuite/ld-scripts/align.exp @@ -53,3 +53,7 @@ if ![is_aout_format] { } run_dump_test align2c set LDFLAGS "$saved_LDFLAGS" + +if { [is_elf_format] && ![is_generic_elf] } { + run_dump_test pr23571 +} diff --git a/ld/testsuite/ld-scripts/pr23571.d b/ld/testsuite/ld-scripts/pr23571.d new file mode 100644 index 00000000000..adf479660bb --- /dev/null +++ b/ld/testsuite/ld-scripts/pr23571.d @@ -0,0 +1,10 @@ +#source: align2a.s +#ld: -T pr23571.t -z common-page-size=0x1000 +#objdump: -h -w + +.*: +file format .* + +Sections: +Idx Name +Size +VMA +LMA +File off +Algn +Flags + +0 \.text +[0-9a-f]* +0+1000 +0+1000 .* + +1 \.data +[0-9a-f]* +0+2000 +0+2000 +[0-9a-f]* +2\*\*12 .* diff --git a/ld/testsuite/ld-scripts/pr23571.t b/ld/testsuite/ld-scripts/pr23571.t new file mode 100644 index 00000000000..290cdf50df9 --- /dev/null +++ b/ld/testsuite/ld-scripts/pr23571.t @@ -0,0 +1,11 @@ +SECTIONS +{ + .text CONSTANT(COMMONPAGESIZE) : { + *(.text) + } + + .data : ALIGN(CONSTANT(COMMONPAGESIZE)) { + *(.data) + } + /DISCARD/ : {*(*)} +} -- 2.30.2